A classical mechanics problem by Mohamed Tolba

A roller is placed over an inclined rough plane under the effect of a moment that causes it to start rolling ...Case(1).....The same roller is placed on the same rough plane but instead of the moment there is a force affecting this roller and its direction is parallel to the plane ...Case(2) ... what do you think is the direction of the friction force in both cases in the limiting equilibrium of roller in reference with the direction of motion ?